1. Field of the Invention
This invention relates to surgical stapling apparatus, and more particularly, to surgical apparatus for performing sequential operations such as tissue clamping, staple forming and/or tissue cutting.
2. Description of Related Art
Surgical stapling apparatus are known wherein tissue is first grasped or clamped between opposing jaw structure and then fastened by means of fasteners. In some instruments a knife is provided to cut tissue which has been joined. The fasteners are typically in the form of surgical staples. However, two part polymeric type fasteners are also known.
Instruments for this purpose can comprise two elongated fingers which are respectively used to capture or clamp tissue. Typically, one of the fingers carries a disposable cartridge housing wherein a plurality of staples are arranged in at least two lateral rows while the other finger comprises an anvil for curling the staple legs into a hook-like configuration upon their being driven against the anvil. The stapling operation is effected by a pusher which travels longitudinally along the cartridge carrying finger, with the pusher acting upon the staples to place rows of staples in body tissue. A knife may be optionally positioned in such a manner so as to operate sequentially immediately behind the pusher, and laterally positioned between the staple rows to longitudinally cut and/or open the stapled tissue between the rows of staples. Such instruments are disclosed in Bobrov et al. (U.S. Pat. No. 3,079,606) and Green (U.S. Pat. No. 3,490,675). These instruments comprise apparatus for simultaneously making a longitudinal incision and applying a row of staples on both sides of the incision.
A later development disclosed in Green (U.S. Pat. No. 3,499,591) applies a double row of staples on each side of the incision. This is accomplished by a cartridge assembly wherein a cam member moves within a guide path between two sets of staggered staple carrying grooves. Staple drive members located within the grooves each have two staple pusher plates, and sloping surfaces disposed within the guide path so as to be contacted by the longitudinally moving cam and be driven along the groove to effect ejection of two staples.
The cartridge assemblies typically come in a plurality of sizes, each varying in both length and number of staples contained therein. Depending on the procedure to be performed, the surgeon must select the appropriate cartridge assembly. No provision is currently available to adjust the firing means of the instrument itself so that a wide variety of staple driving sequences may be accomplished using a single staple cartridge assembly.
The instruments described above were all designed to be used in surgical procedures wherein surgeons have direct manual access to the operation site. However, in endoscopic or laparoscopic procedures surgery is performed through a small incision or through narrow cannulae inserted through small entrance wounds in the skin. In order to address the specific needs of endoscopic and/or laparoscopic surgical procedures, an endoscopic surgical stapling apparatus such as that shown in Green et al. (U.S. Pat. No. 5,040,715) has been developed. This apparatus is well suited for such procedures and incorporates a distal end having an anvil and staple cartridge assembly and a manually operated handle assembly interconnected by an endoscopic portion which permits the instrument to be inserted into a cannula and be remotely operated by the surgeon.
An object of the present invention is to provide a surgical apparatus that provides a full range of remotely actuated movements to the distal working members of the apparatus to facilitate interaction with and manipulation of tissue.